chore(release): 5.1.0 [skip ci]

# [5.1.0](https://github.com/revanced/revanced-patcher/compare/v5.0.1...v5.1.0) (2022-09-26)

### Features

* RwLock for opening files in `DomFileEditor` ([db4348c](db4348c4fa))

.github/ISSUE_TEMPLATE/bug-issue.yml

@@ -0,0 +1,72 @@
+name: 🐞 Bug report
+description: Report a very clearly broken issue.
+title: 'bug: <title>'
+labels: [bug]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        # ReVanced bug report
+
+        Important to note that your issue may have already been reported before. Please check for existing issues [here](https://github.com/revanced/revanced-patcher/labels/bug).
+
+  - type: dropdown
+    attributes:
+      label: Type
+      options:
+        - Crash
+        - Cosmetic
+        - Other
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Bug description
+      description: How did you find the bug? Any additional details that might help?
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Steps to reproduce
+      description: Add the steps to reproduce this bug including your environment.
+      placeholder: Step 1. Download some files. Step 2. ...
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Relevant log output
+      description: Please copy and paste any relevant log output. This will be automatically formatted into code, so no need for backticks.
+      render: shell
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Screenshots or videos
+      description: Add screenshots or videos that show the bug here.
+      placeholder: Drag and drop the screenshots/videos into this box.
+    validations:
+      required: false
+  - type: textarea
+    attributes:
+      label: Solution
+      description: If applicable, add a possible solution.
+    validations:
+      required: false
+  - type: textarea
+    attributes:
+      label: Additional context
+      description: Add additional context here.
+    validations:
+      required: false
+  - type: checkboxes
+    id: acknowledgements
+    attributes:
+      label: Acknowledgements
+      description: Your issue will be closed if you haven't done these steps.
+      options:
+        - label: I have searched the existing issues and this is a new and no duplicate or related to another open issue.
+          required: true
+        - label: I have written a short but informative title.
+          required: true
+        - label: I filled out all of the requested information in this issue properly.
+          required: true

.github/ISSUE_TEMPLATE/bug-report.md

@@ -1,24 +0,0 @@
----
-name: Bug report
-about: Create a bug report on the patcher. Do not submit suggestions for patches here.
-title: 'problem: some problem'
-labels: bug
-assignees: oSumAtrIX, Sculas
-
----
-
-## 🐞 Issue
-
-<!-- Describe your issue in detail here -->
-
-## ⚙ Reproduce
-
-<!-- Include your environment and steps to reproduce the issue as detailed as possible -->
-
-## 🛠 Solution
-
-<!-- If applicable, add a possible solution -->
-
-## ⚠ Additional context
-
-<!-- Add any other context about the problem here -->

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,8 @@
+blank_issues_enabled: false
+contact_links:
+  - name: 📃 Documentation
+    url: https://github.com/revanced/revanced-documentation/
+    about: Don't know how or where to start? Check out our documentation!
+  - name: 🗨 Discussions
+    url: https://github.com/revanced/revanced-suggestions/discussions
+    about: Got something you think should change or be added? Search for or start a new discussion!

.github/ISSUE_TEMPLATE/feature-issue.yml

@@ -0,0 +1,58 @@
+name: ⭐ Feature request
+description: Create a detailed feature request.
+title: 'feat: <title>'
+labels: [feature-request]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        # ReVanced feature request
+        
+        Do not submit requests for patches here. Please submit them [here](https://github.com/orgs/revanced/discussions/categories/patches) instead.
+        Important to note that your feature request may have already been made before. Please check for existing feature requests [here](https://github.com/revanced/revanced-patcher/labels/feature-request).
+
+  - type: dropdown
+    attributes:
+      label: Type
+      options:
+        - Functionality
+        - Cosmetic
+        - Other
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Issue
+      description: What is the current problem. Why does it require a feature request?
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Feature
+      description: Describe your feature in detail. How does it solve the issue?
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Motivation
+      description: Why should your feature should be considered?
+    validations:
+      required: true
+  - type: textarea
+    attributes:
+      label: Additional context
+      description: Add additional context here.
+    validations:
+      required: false
+  - type: checkboxes
+    id: acknowledgements
+    attributes:
+      label: Acknowledgements
+      description: Your issue will be closed if you haven't done these steps.
+      options:
+        - label: I have searched the existing issues and this is a new and no duplicate or related to another open issue.
+          required: true
+        - label: I have written a short but informative title.
+          required: true
+        - label: I filled out all of the requested information in this issue properly.
+          required: true

.github/ISSUE_TEMPLATE/feature_request.md

@@ -1,24 +0,0 @@
----
-name: Feature request
-about: Suggest a change for the patcher. Do not submit suggestions for patches here.
-title: 'feat: some feature'
-labels: feature-request
-assignees: ''
-
----
-
-## 🐞 Issue
-
-<!-- Explain here, what the current problem is and why it leads you to request a feature change -->
-
-## ❗ Solution
-
-<!-- Explain how your current issue can be solved -->
-
-## ❓ Motivation
-
-<!-- Explain why your feature should be considered -->
-
-## ⚠ Additional context
-
-<!-- Add any other context or screenshots about the feature request here -->

.idea/.gitignore

@@ -6,3 +6,4 @@
 # Datasource local storage ignored files
 /dataSources/
 /dataSources.local.xml
+/kotlinc.xml

README.md

@@ -1 +1,2 @@
 # Patcher
+Patcher framework used in the ReVanced project.

build.gradle.kts

@@ -24,8 +24,9 @@ dependencies {
     implementation("xpp3:xpp3:1.1.4c")
     implementation("org.smali:smali:2.5.2")
     implementation("app.revanced:multidexlib2:2.5.2.r2")
-    implementation("org.apktool:apktool-lib:2.6.9-SNAPSHOT")
+    implementation("org.apktool:apktool-lib:2.8.1-SNAPSHOT")
 
+    implementation(kotlin("reflect"))
     testImplementation(kotlin("test"))
 }
 
@@ -36,6 +37,9 @@ tasks {
             events("PASSED", "SKIPPED", "FAILED")
         }
     }
+    processResources {
+        expand("projectVersion" to project.version)
+    }
 }
 
 java {

gradle.properties

@@ -1,2 +1,2 @@
 kotlin.code.style = official
-version = 2.5.1
+version = 5.1.0

src/main/kotlin/app/revanced/patcher/annotation/CompatibilityAnnotation.kt

@@ -24,5 +24,5 @@ annotation class Compatibility(
 @MustBeDocumented
 annotation class Package(
     val name: String,
-    val versions: Array<String>
+    val versions: Array<String> = [],
-)
+)

src/main/kotlin/app/revanced/patcher/annotation/Deprecated.kt

@@ -0,0 +1,19 @@
+package app.revanced.patcher.annotation
+
+import app.revanced.patcher.data.Data
+import app.revanced.patcher.patch.Patch
+import kotlin.reflect.KClass
+
+/**
+ * Declares a [Patch] deprecated for removal.
+ * @param reason The reason why the patch is deprecated.
+ * @param replacement The replacement for the deprecated patch, if any.
+ */
+@Target(AnnotationTarget.CLASS)
+@Retention(AnnotationRetention.RUNTIME)
+@MustBeDocumented
+annotation class PatchDeprecated(
+    val reason: String,
+    val replacement: KClass<out Patch<Data>> = Patch::class
+    // Values cannot be nullable in annotations, so this will have to do.
+)

src/main/kotlin/app/revanced/patcher/annotation/SincePatcher.kt

@@ -0,0 +1,13 @@
+package app.revanced.patcher.annotation
+
+import app.revanced.patcher.patch.Patch
+import app.revanced.patcher.Patcher
+
+/**
+ * Declares a [Patch] deprecated for removal.
+ * @param version The minimum version of the [Patcher] this [Patch] supports.
+ */
+@Target(AnnotationTarget.CLASS)
+@Retention(AnnotationRetention.RUNTIME)
+@MustBeDocumented
+annotation class SincePatcher(val version: String)

src/main/kotlin/app/revanced/patcher/data/impl/ResourceData.kt

@@ -19,31 +19,85 @@ class ResourceData(private val resourceCacheDirectory: File) : Data, Iterable<Fi
     override fun iterator() = resourceCacheDirectory.walkTopDown().iterator()
 
     inner class XmlFileHolder {
-        operator fun get(inputStream: InputStream, outputStream: OutputStream) =
+        operator fun get(inputStream: InputStream) =
-            DomFileEditor(inputStream, lazyOf(outputStream))
+            DomFileEditor(inputStream)
+
+        operator fun get(path: String): DomFileEditor {
+            return DomFileEditor(this@ResourceData[path])
+        }
 
-        operator fun get(path: String) = DomFileEditor(this@ResourceData[path])
     }
 }
 
+/**
+ * Wrapper for a file that can be edited as a dom document.
+ * Note: This constructor does not check for locks to the file when writing. Use the secondary constructor.
+ *
+ * @param inputStream the input stream to read the xml file from.
+ * @param outputStream the output stream to write the xml file to. If null, the file will be read only.
+ *
+ */
 class DomFileEditor internal constructor(
     private val inputStream: InputStream,
-    private val outputStream: Lazy<OutputStream>,
+    private val outputStream: Lazy<OutputStream>? = null,
 ) : Closeable {
+    // path to the xml file to unlock the resource when closing the editor
+    private var filePath: String? = null
+    private var closed: Boolean = false
+
+    /**
+     * The document of the xml file
+     */
     val file: Document = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(inputStream)
         .also(Document::normalize)
 
+
     // lazily open an output stream
     // this is required because when constructing a DomFileEditor the output stream is created along with the input stream, which is not allowed
     // the workaround is to lazily create the output stream. This way it would be used after the input stream is closed, which happens in the constructor
-    constructor(file: File) : this(file.inputStream(), lazy { file.outputStream() })
+    constructor(file: File) : this(file.inputStream(), lazy { file.outputStream() }) {
-
+        // increase the lock
-    override fun close() {
+        locks.merge(file.path, 1, Integer::sum)
-        val result = StreamResult(outputStream.value)
+        filePath = file.path
-        TransformerFactory.newInstance().newTransformer().transform(DOMSource(file), result)
-
-        inputStream.close()
-        outputStream.value.close()
     }
 
+    /**
+     * Closes the editor. Write backs and decreases the lock count.
+     * Note: Will not write back to the file if the file is still locked.
+     */
+    override fun close() {
+        if (closed) return
+
+        inputStream.close()
+
+        // if the output stream is not null, do not close it
+        outputStream?.let {
+            // prevent writing to same file, if it is being locked
+            // isLocked will be false if the editor was created through a stream
+            val isLocked = filePath?.let { path ->
+                val isLocked = locks[path]!! > 1
+                // decrease the lock count if the editor was opened for a file
+                locks.merge(path, -1, Integer::sum)
+                isLocked
+            } ?: false
+
+            // if unlocked, write back to the file
+            if (!isLocked) {
+                it.value.use { stream ->
+                    val result = StreamResult(stream)
+                    TransformerFactory.newInstance().newTransformer().transform(DOMSource(file), result)
+                }
+
+                it.value.close()
+                return
+            }
+        }
+
+        closed = true
+    }
+
+    private companion object {
+        // map of concurrent open files
+        val locks = mutableMapOf<String, Int>()
+    }
 }

src/main/kotlin/app/revanced/patcher/extensions/AnnotationExtensions.kt

@@ -1,13 +1,15 @@
 package app.revanced.patcher.extensions
 
-import app.revanced.patcher.annotation.Compatibility
+import app.revanced.patcher.annotation.*
-import app.revanced.patcher.annotation.Description
-import app.revanced.patcher.annotation.Name
-import app.revanced.patcher.annotation.Version
 import app.revanced.patcher.data.Data
 import app.revanced.patcher.fingerprint.method.impl.MethodFingerprint
+import app.revanced.patcher.patch.OptionsContainer
 import app.revanced.patcher.patch.Patch
+import app.revanced.patcher.patch.PatchOptions
 import kotlin.reflect.KClass
+import kotlin.reflect.KVisibility
+import kotlin.reflect.full.companionObject
+import kotlin.reflect.full.companionObjectInstance
 
 /**
  * Recursively find a given annotation on a class.
@@ -36,13 +38,33 @@ private fun <T : Annotation> Class<*>.findAnnotationRecursively(
 }
 
 object PatchExtensions {
-    val Class<out Patch<Data>>.patchName: String
+    val Class<*>.patchName: String
         get() = recursiveAnnotation(Name::class)?.name ?: this.javaClass.simpleName
     val Class<out Patch<Data>>.version get() = recursiveAnnotation(Version::class)?.version
     val Class<out Patch<Data>>.include get() = recursiveAnnotation(app.revanced.patcher.patch.annotations.Patch::class)!!.include
     val Class<out Patch<Data>>.description get() = recursiveAnnotation(Description::class)?.description
-    val Class<out Patch<Data>>.dependencies get() = recursiveAnnotation(app.revanced.patcher.patch.annotations.Dependencies::class)?.dependencies
+    val Class<out Patch<Data>>.dependencies get() = recursiveAnnotation(app.revanced.patcher.patch.annotations.DependsOn::class)?.dependencies
     val Class<out Patch<Data>>.compatiblePackages get() = recursiveAnnotation(Compatibility::class)?.compatiblePackages
+    val Class<out Patch<Data>>.options: PatchOptions?
+        get() = kotlin.companionObject?.let { cl ->
+            if (cl.visibility != KVisibility.PUBLIC) return null
+            kotlin.companionObjectInstance?.let {
+                (it as? OptionsContainer)?.options
+            }
+        }
+    val Class<out Patch<Data>>.deprecated: Pair<String, KClass<out Patch<Data>>?>?
+        get() = recursiveAnnotation(PatchDeprecated::class)?.let {
+            it.reason to it.replacement.let { cl ->
+                if (cl == Patch::class) null else cl
+            }
+        }
+    val Class<out Patch<Data>>.sincePatcherVersion get() = recursiveAnnotation(SincePatcher::class)?.version
+
+    @JvmStatic
+    fun Class<out Patch<Data>>.dependsOn(patch: Class<out Patch<Data>>): Boolean {
+        if (this.patchName == patch.patchName) throw IllegalArgumentException("thisval and patch may not be the same")
+        return this.dependencies?.any { it.java.patchName == this@dependsOn.patchName } == true
+    }
 }
 
 object MethodFingerprintExtensions {

src/main/kotlin/app/revanced/patcher/extensions/Extensions.kt

@@ -16,7 +16,6 @@ import org.jf.dexlib2.iface.instruction.Instruction
 import org.jf.dexlib2.iface.reference.MethodReference
 import org.jf.dexlib2.immutable.ImmutableMethod
 import org.jf.dexlib2.immutable.ImmutableMethodImplementation
-import org.jf.dexlib2.util.MethodUtil
 import java.io.OutputStream
 
 infix fun AccessFlags.or(other: AccessFlags) = this.value or other.value
@@ -47,16 +46,14 @@ fun MutableMethodImplementation.removeInstructions(index: Int, count: Int) {
 }
 
 /**
- * Compare a method to another, considering constructors and parameters.
+ * Compare a method to another, considering name and parameters.
  * @param otherMethod The method to compare against.
  * @return True if the methods match given the conditions.
  */
 fun Method.softCompareTo(otherMethod: MethodReference): Boolean {
-    if (MethodUtil.isConstructor(this) && !parametersEqual(
+    return this.name == otherMethod.name && parametersEqual(
-            this.parameterTypes, otherMethod.parameterTypes
+        this.parameterTypes, otherMethod.parameterTypes
-        )
+    )
-    ) return false
-    return this.name == otherMethod.name
 }
 
 /**

src/main/kotlin/app/revanced/patcher/fingerprint/method/utils/MethodFingerprintUtils.kt

@@ -1,158 +0,0 @@
-package app.revanced.patcher.fingerprint.method.utils
-
-import app.revanced.patcher.data.impl.BytecodeData
-import app.revanced.patcher.extensions.MethodFingerprintExtensions.fuzzyPatternScanMethod
-import app.revanced.patcher.extensions.MethodFingerprintExtensions.fuzzyScanThreshold
-import app.revanced.patcher.extensions.parametersEqual
-import app.revanced.patcher.fingerprint.method.annotation.FuzzyPatternScanMethod
-import app.revanced.patcher.fingerprint.method.impl.MethodFingerprint
-import app.revanced.patcher.fingerprint.method.impl.MethodFingerprintResult
-import app.revanced.patcher.fingerprint.method.impl.PatternScanResult
-import org.jf.dexlib2.Opcode
-import org.jf.dexlib2.iface.ClassDef
-import org.jf.dexlib2.iface.Method
-import org.jf.dexlib2.iface.instruction.Instruction
-import org.jf.dexlib2.iface.instruction.ReferenceInstruction
-import org.jf.dexlib2.iface.reference.StringReference
-
-/**
- * Utility class for [MethodFingerprint]
- */
-object MethodFingerprintUtils {
-    /**
-     * Resolve a list of [MethodFingerprint] against a list of [ClassDef].
-     * @param context The classes on which to resolve the [MethodFingerprint].
-     * @param forData The [BytecodeData] to host proxies.
-     * @return True if the resolution was successful, false otherwise.
-     */
-    fun Iterable<MethodFingerprint>.resolve(forData: BytecodeData, context: Iterable<ClassDef>) {
-        for (fingerprint in this) // For each fingerprint
-            classes@ for (classDef in context) // search through all classes for the fingerprint
-                if (fingerprint.resolve(forData, classDef))
-                    break@classes // if the resolution succeeded, continue with the next fingerprint
-    }
-
-    /**
-     * Resolve a [MethodFingerprint] against a [ClassDef].
-     * @param context The class on which to resolve the [MethodFingerprint].
-     * @param forData The [BytecodeData] to host proxies.
-     * @return True if the resolution was successful, false otherwise.
-     */
-    fun MethodFingerprint.resolve(forData: BytecodeData, context: ClassDef): Boolean {
-        for (method in context.methods)
-            if (this.resolve(forData, method, context))
-                return true
-        return false
-    }
-
-    /**
-     * Resolve a [MethodFingerprint] against a [Method].
-     * @param context The context on which to resolve the [MethodFingerprint].
-     * @param classDef The class of the matching [Method].
-     * @param forData The [BytecodeData] to host proxies.
-     * @return True if the resolution was successful, false otherwise.
-     */
-    fun MethodFingerprint.resolve(forData: BytecodeData, context: Method, classDef: ClassDef): Boolean {
-        val methodFingerprint = this
-
-        if (methodFingerprint.returnType != null && !context.returnType.startsWith(methodFingerprint.returnType))
-            return false
-
-        if (methodFingerprint.access != null && methodFingerprint.access != context.accessFlags)
-            return false
-
-
-        if (methodFingerprint.parameters != null && !parametersEqual(
-                methodFingerprint.parameters, // TODO: parseParameters()
-                context.parameterTypes
-            )
-        ) return false
-
-        if (methodFingerprint.customFingerprint != null && !methodFingerprint.customFingerprint!!(context))
-            return false
-
-        if (methodFingerprint.strings != null) {
-            val implementation = context.implementation ?: return false
-
-            val stringsList = methodFingerprint.strings.toMutableList()
-
-            implementation.instructions.forEach { instruction ->
-                if (instruction.opcode.ordinal != Opcode.CONST_STRING.ordinal) return@forEach
-
-                val string = ((instruction as ReferenceInstruction).reference as StringReference).string
-                val index = stringsList.indexOfFirst { it == string }
-                if (index != -1) stringsList.removeAt(index)
-            }
-
-            if (stringsList.isNotEmpty()) return false
-        }
-
-        val patternScanResult = if (methodFingerprint.opcodes != null) {
-            context.implementation?.instructions ?: return false
-
-            context.patternScan(methodFingerprint) ?: return false
-        } else null
-
-        methodFingerprint.result = MethodFingerprintResult(context, classDef, patternScanResult, forData)
-
-        return true
-    }
-
-    private fun Method.patternScan(
-        fingerprint: MethodFingerprint
-    ): PatternScanResult? {
-        val instructions = this.implementation!!.instructions
-        val fingerprintFuzzyPatternScanThreshold = fingerprint.fuzzyScanThreshold
-
-        val pattern = fingerprint.opcodes!!
-        val instructionLength = instructions.count()
-        val patternLength = pattern.count()
-
-        for (index in 0 until instructionLength) {
-            var patternIndex = 0
-            var threshold = fingerprintFuzzyPatternScanThreshold
-
-            while (index + patternIndex < instructionLength) {
-                val originalOpcode = instructions.elementAt(index + patternIndex).opcode
-                val patternOpcode = pattern.elementAt(patternIndex)
-
-                if (patternOpcode != null && patternOpcode.ordinal != originalOpcode.ordinal) {
-                    // reaching maximum threshold (0) means,
-                    // the pattern does not match to the current instructions
-                    if (threshold-- == 0) break
-                }
-
-                if (patternIndex < patternLength - 1) {
-                    // if the entire pattern has not been scanned yet
-                    // continue the scan
-                    patternIndex++
-                    continue
-                }
-                // the pattern is valid, generate warnings if fuzzyPatternScanMethod is FuzzyPatternScanMethod
-                val result = PatternScanResult(index, index + patternIndex)
-                if (fingerprint.fuzzyPatternScanMethod !is FuzzyPatternScanMethod) return result
-                result.warnings = result.createWarnings(pattern, instructions)
-
-                return result
-            }
-        }
-
-        return null
-    }
-}
-
-private fun PatternScanResult.createWarnings(
-    pattern: Iterable<Opcode?>, instructions: Iterable<Instruction>
-) = buildList {
-    for ((patternIndex, instructionIndex) in (this@createWarnings.startIndex until this@createWarnings.endIndex).withIndex()) {
-        val originalOpcode = instructions.elementAt(instructionIndex).opcode
-        val patternOpcode = pattern.elementAt(patternIndex)
-
-        if (patternOpcode == null || patternOpcode.ordinal == originalOpcode.ordinal) continue
-
-        this.add(PatternScanResult.Warning(originalOpcode, patternOpcode, instructionIndex, patternIndex))
-    }
-}
-
-private operator fun ClassDef.component1() = this
-private operator fun ClassDef.component2() = this.methods

src/main/kotlin/app/revanced/patcher/patch/Patch.kt

@@ -3,16 +3,32 @@ package app.revanced.patcher.patch
 import app.revanced.patcher.data.Data
 import app.revanced.patcher.patch.impl.BytecodePatch
 import app.revanced.patcher.patch.impl.ResourcePatch
-
+import java.io.Closeable
 
 /**
  * A ReVanced patch.
+ *
  * Can either be a [ResourcePatch] or a [BytecodePatch].
+ * If it implements [Closeable], it will be closed after all patches have been executed.
+ * Closing will be done in reverse execution order.
  */
 abstract class Patch<out T : Data> {
-
     /**
      * The main function of the [Patch] which the patcher will call.
      */
     abstract fun execute(data: @UnsafeVariance T): PatchResult
+}
+
+abstract class OptionsContainer {
+    /**
+     * A list of [PatchOption]s.
+     * @see PatchOptions
+     */
+    @Suppress("MemberVisibilityCanBePrivate")
+    val options = PatchOptions()
+
+    protected fun <T> option(opt: PatchOption<T>): PatchOption<T> {
+        options.register(opt)
+        return opt
+    }
 }

src/main/kotlin/app/revanced/patcher/patch/PatchOption.kt

@@ -0,0 +1,248 @@
+@file:Suppress("CanBeParameter", "MemberVisibilityCanBePrivate", "UNCHECKED_CAST")
+
+package app.revanced.patcher.patch
+
+import java.nio.file.Path
+import kotlin.io.path.pathString
+import kotlin.reflect.KProperty
+
+class NoSuchOptionException(val option: String) : Exception("No such option: $option")
+class IllegalValueException(val value: Any?) : Exception("Illegal value: $value")
+class InvalidTypeException(val got: String, val expected: String) :
+    Exception("Invalid option value type: $got, expected $expected")
+
+object RequirementNotMetException : Exception("null was passed into an option that requires a value")
+
+/**
+ * A registry for an array of [PatchOption]s.
+ * @param options An array of [PatchOption]s.
+ */
+class PatchOptions(vararg options: PatchOption<*>) : Iterable<PatchOption<*>> {
+    private val register = mutableMapOf<String, PatchOption<*>>()
+
+    init {
+        options.forEach { register(it) }
+    }
+
+    internal fun register(option: PatchOption<*>) {
+        if (register.containsKey(option.key)) {
+            throw IllegalStateException("Multiple options found with the same key")
+        }
+        register[option.key] = option
+    }
+
+    /**
+     * Get a [PatchOption] by its key.
+     * @param key The key of the [PatchOption].
+     */
+    @JvmName("getUntyped")
+    operator fun get(key: String) = register[key] ?: throw NoSuchOptionException(key)
+
+    /**
+     * Get a [PatchOption] by its key.
+     * @param key The key of the [PatchOption].
+     */
+    inline operator fun <reified T> get(key: String): PatchOption<T> {
+        val opt = get(key)
+        if (opt.value !is T) throw InvalidTypeException(
+            opt.value?.let { it::class.java.canonicalName } ?: "null",
+            T::class.java.canonicalName
+        )
+        return opt as PatchOption<T>
+    }
+
+    /**
+     * Set the value of a [PatchOption].
+     * @param key The key of the [PatchOption].
+     * @param value The value you want it to be.
+     * Please note that using the wrong value type results in a runtime error.
+     */
+    inline operator fun <reified T> set(key: String, value: T) {
+        val opt = get<T>(key)
+        if (opt.value !is T) throw InvalidTypeException(
+            T::class.java.canonicalName,
+            opt.value?.let { it::class.java.canonicalName } ?: "null"
+        )
+        opt.value = value
+    }
+
+    /**
+     * Sets the value of a [PatchOption] to `null`.
+     * @param key The key of the [PatchOption].
+     */
+    fun nullify(key: String) {
+        get(key).value = null
+    }
+
+    override fun iterator() = register.values.iterator()
+}
+
+/**
+ * A [Patch] option.
+ * @param key Unique identifier of the option. Example: _`settings.microg.enabled`_
+ * @param default The default value of the option.
+ * @param title A human-readable title of the option. Example: _MicroG Settings_
+ * @param description A human-readable description of the option. Example: _Settings integration for MicroG._
+ * @param required Whether the option is required.
+ */
+@Suppress("MemberVisibilityCanBePrivate")
+sealed class PatchOption<T>(
+    val key: String,
+    default: T?,
+    val title: String,
+    val description: String,
+    val required: Boolean,
+    val validator: (T?) -> Boolean
+) {
+    var value: T? = default
+        get() {
+            if (field == null && required) {
+                throw RequirementNotMetException
+            }
+            return field
+        }
+        set(value) {
+            if (value == null && required) {
+                throw RequirementNotMetException
+            }
+            if (!validator(value)) {
+                throw IllegalValueException(value)
+            }
+            field = value
+        }
+
+    /**
+     * Gets the value of the option.
+     * Please note that using the wrong value type results in a runtime error.
+     */
+    @JvmName("getValueTyped")
+    inline operator fun <reified V> getValue(thisRef: Nothing?, property: KProperty<*>): V? {
+        if (value !is V?) throw InvalidTypeException(
+            V::class.java.canonicalName,
+            value?.let { it::class.java.canonicalName } ?: "null"
+        )
+        return value as? V?
+    }
+
+    operator fun getValue(thisRef: Any?, property: KProperty<*>) = value
+
+    /**
+     * Gets the value of the option.
+     * Please note that using the wrong value type results in a runtime error.
+     */
+    @JvmName("setValueTyped")
+    inline operator fun <reified V> setValue(thisRef: Nothing?, property: KProperty<*>, new: V) {
+        if (value !is V) throw InvalidTypeException(
+            V::class.java.canonicalName,
+            value?.let { it::class.java.canonicalName } ?: "null"
+        )
+        value = new as T
+    }
+
+    operator fun setValue(thisRef: Any?, property: KProperty<*>, new: T?) {
+        value = new
+    }
+
+    /**
+     * A [PatchOption] representing a [String].
+     * @see PatchOption
+     */
+    class StringOption(
+        key: String,
+        default: String?,
+        title: String,
+        description: String,
+        required: Boolean = false,
+        validator: (String?) -> Boolean = { true }
+    ) : PatchOption<String>(
+        key, default, title, description, required, validator
+    )
+
+    /**
+     * A [PatchOption] representing a [Boolean].
+     * @see PatchOption
+     */
+    class BooleanOption(
+        key: String,
+        default: Boolean?,
+        title: String,
+        description: String,
+        required: Boolean = false,
+        validator: (Boolean?) -> Boolean = { true }
+    ) : PatchOption<Boolean>(
+        key, default, title, description, required, validator
+    )
+
+    /**
+     * A [PatchOption] with a list of allowed options.
+     * @param options A list of allowed options for the [ListOption].
+     * @see PatchOption
+     */
+    sealed class ListOption<E>(
+        key: String,
+        default: E?,
+        val options: Iterable<E>,
+        title: String,
+        description: String,
+        required: Boolean = false,
+        validator: (E?) -> Boolean = { true }
+    ) : PatchOption<E>(
+        key, default, title, description, required, {
+            (it?.let { it in options } ?: true) && validator(it)
+        }
+    ) {
+        init {
+            if (default != null && default !in options) {
+                throw IllegalStateException("Default option must be an allowed option")
+            }
+        }
+    }
+
+    /**
+     * A [ListOption] of type [String].
+     * @see ListOption
+     */
+    class StringListOption(
+        key: String,
+        default: String?,
+        options: Iterable<String>,
+        title: String,
+        description: String,
+        required: Boolean = false,
+        validator: (String?) -> Boolean = { true }
+    ) : ListOption<String>(
+        key, default, options, title, description, required, validator
+    )
+
+    /**
+     * A [ListOption] of type [Int].
+     * @see ListOption
+     */
+    class IntListOption(
+        key: String,
+        default: Int?,
+        options: Iterable<Int>,
+        title: String,
+        description: String,
+        required: Boolean = false,
+        validator: (Int?) -> Boolean = { true }
+    ) : ListOption<Int>(
+        key, default, options, title, description, required, validator
+    )
+
+    /**
+     * A [PatchOption] representing a [Path], backed by a [String].
+     * The validator passes a [String], if you need a [Path] you will have to convert it yourself.
+     * @see PatchOption
+     */
+    class PathOption(
+        key: String,
+        default: Path?,
+        title: String,
+        description: String,
+        required: Boolean = false,
+        validator: (String?) -> Boolean = { true }
+    ) : PatchOption<String>(
+        key, default?.pathString, title, description, required, validator
+    )
+}

src/main/kotlin/app/revanced/patcher/patch/annotations/PatchAnnotation.kt

@@ -19,6 +19,6 @@ annotation class Patch(val include: Boolean = true)
 @Target(AnnotationTarget.CLASS)
 @Retention(AnnotationRetention.RUNTIME)
 @MustBeDocumented
-annotation class Dependencies(
+annotation class DependsOn(
     val dependencies: Array<KClass<out Patch<Data>>> = []
 )

src/main/kotlin/app/revanced/patcher/util/VersionReader.kt

@@ -0,0 +1,18 @@
+package app.revanced.patcher.util
+
+import java.util.*
+
+internal object VersionReader {
+    @JvmStatic
+    private val props = Properties().apply {
+        load(
+            VersionReader::class.java.getResourceAsStream("/revanced-patcher/version.properties")
+                ?: throw IllegalStateException("Could not load version.properties")
+        )
+    }
+
+    @JvmStatic
+    fun read(): String {
+        return props.getProperty("version") ?: throw IllegalStateException("Version not found")
+    }
+}

src/main/kotlin/app/revanced/patcher/util/dex/DexFile.kt

@@ -5,6 +5,6 @@ import java.io.InputStream
 /**
  * Wrapper for dex files.
  * @param name The original name of the dex file.
- * @param dexFileInputStream The dex file as [InputStream].
+ * @param stream The dex file as [InputStream].
  */
-data class DexFile(val name: String, val dexFileInputStream: InputStream)
+data class DexFile(val name: String, val stream: InputStream)

src/main/kotlin/app/revanced/patcher/util/patch/PatchBundle.kt

@@ -1,17 +1,17 @@
-package app.revanced.patcher.util.patch.base
+package app.revanced.patcher.util.patch
 
 import app.revanced.patcher.data.Data
 import app.revanced.patcher.patch.Patch
 import java.io.File
 
 /**
- * @param patchBundlePath The path to the patch bundle.
+ * @param path The path to the patch bundle.
  */
-abstract class PatchBundle(patchBundlePath: String) : File(patchBundlePath) {
+abstract class PatchBundle(path: String) : File(path) {
     internal fun loadPatches(classLoader: ClassLoader, classNames: Iterator<String>) = buildList {
-        classNames.forEach { className ->
+        for (className in classNames) {
             val clazz = classLoader.loadClass(className)
-            if (!clazz.isAnnotationPresent(app.revanced.patcher.patch.annotations.Patch::class.java)) return@forEach
+            if (!clazz.isAnnotationPresent(app.revanced.patcher.patch.annotations.Patch::class.java)) continue
             @Suppress("UNCHECKED_CAST") this.add(clazz as Class<out Patch<Data>>)
         }
     }

src/main/kotlin/app/revanced/patcher/util/patch/StringIterator.kt

@@ -1,4 +1,4 @@
-package app.revanced.patcher.util.patch.util
+package app.revanced.patcher.util.patch
 
 internal class StringIterator<T, I : Iterator<T>>(
     private val iterator: I,

src/main/kotlin/app/revanced/patcher/util/patch/impl/DexPatchBundle.kt

@@ -1,7 +1,7 @@
-package app.revanced.patcher.util.patch.implementation
+package app.revanced.patcher.util.patch.impl
 
-import app.revanced.patcher.util.patch.base.PatchBundle
+import app.revanced.patcher.util.patch.PatchBundle
-import app.revanced.patcher.util.patch.util.StringIterator
+import app.revanced.patcher.util.patch.StringIterator
 import org.jf.dexlib2.DexFileFactory
 
 /**

src/main/kotlin/app/revanced/patcher/util/patch/impl/JarPatchBundle.kt

@@ -1,7 +1,7 @@
-package app.revanced.patcher.util.patch.implementation
+package app.revanced.patcher.util.patch.impl
 
-import app.revanced.patcher.util.patch.base.PatchBundle
+import app.revanced.patcher.util.patch.PatchBundle
-import app.revanced.patcher.util.patch.util.StringIterator
+import app.revanced.patcher.util.patch.StringIterator
 import java.net.URLClassLoader
 import java.util.jar.JarFile
 

src/main/resources/revanced-patcher/version.properties

@@ -0,0 +1 @@
+version=${projectVersion}

src/test/kotlin/app/revanced/patcher/issues/Issue98.kt

@@ -0,0 +1,18 @@
+package app.revanced.patcher.issues
+
+import app.revanced.patcher.patch.PatchOption
+import org.junit.jupiter.api.Test
+import kotlin.test.assertNull
+
+internal class Issue98 {
+    companion object {
+        var key1: String? by PatchOption.StringOption(
+            "key1", null, "title", "description"
+        )
+    }
+
+    @Test
+    fun `should infer nullable type correctly`() {
+        assertNull(key1)
+    }
+}

src/test/kotlin/app/revanced/patcher/patch/PatchOptionsTest.kt

@@ -0,0 +1,113 @@
+package app.revanced.patcher.patch
+
+import app.revanced.patcher.usage.bytecode.ExampleBytecodePatch
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.assertThrows
+import kotlin.io.path.Path
+import kotlin.io.path.pathString
+import kotlin.test.assertNotEquals
+
+internal class PatchOptionsTest {
+    private val options = ExampleBytecodePatch.options
+
+    @Test
+    fun `should not throw an exception`() {
+        for (option in options) {
+            when (option) {
+                is PatchOption.StringOption -> {
+                    option.value = "Hello World"
+                }
+
+                is PatchOption.BooleanOption -> {
+                    option.value = false
+                }
+
+                is PatchOption.StringListOption -> {
+                    option.value = option.options.first()
+                    for (choice in option.options) {
+                        println(choice)
+                    }
+                }
+
+                is PatchOption.IntListOption -> {
+                    option.value = option.options.first()
+                    for (choice in option.options) {
+                        println(choice)
+                    }
+                }
+
+                is PatchOption.PathOption -> {
+                    option.value = Path("test.txt").pathString
+                }
+            }
+        }
+        val option = options.get<String>("key1")
+        // or: val option: String? by options["key1"]
+        // then you won't need `.value` every time
+        println(option.value)
+        options["key1"] = "Hello, world!"
+        println(option.value)
+    }
+
+    @Test
+    fun `should return a different value when changed`() {
+        var value: String? by options["key1"]
+        val current = value + "" // force a copy
+        value = "Hello, world!"
+        assertNotEquals(current, value)
+    }
+
+    @Test
+    fun `should be able to set value to null`() {
+        // Sadly, doing:
+        // > options["key2"] = null
+        // is not possible because Kotlin
+        // cannot reify the type "Nothing?".
+        // So we have to do this instead:
+        options["key2"] = null as Any?
+        // This is a cleaner replacement for the above:
+        options.nullify("key2")
+    }
+
+    @Test
+    fun `should fail because the option does not exist`() {
+        assertThrows<NoSuchOptionException> {
+            options["this option does not exist"] = 123
+        }
+    }
+
+    @Test
+    fun `should fail because of invalid value type when setting an option`() {
+        assertThrows<InvalidTypeException> {
+            options["key1"] = 123
+        }
+    }
+
+    @Test
+    fun `should fail because of invalid value type when getting an option`() {
+        assertThrows<InvalidTypeException> {
+            options.get<Int>("key1")
+        }
+    }
+
+    @Test
+    fun `should fail because of an illegal value`() {
+        assertThrows<IllegalValueException> {
+            options["key3"] = "this value is not an allowed option"
+        }
+    }
+
+    @Test
+    fun `should fail because the requirement is not met`() {
+        assertThrows<RequirementNotMetException> {
+            options.nullify("key1")
+        }
+    }
+
+    @Test
+    fun `should fail because getting a non-initialized option is illegal`() {
+        assertThrows<RequirementNotMetException> {
+            println(options["key5"].value)
+        }
+    }
+}

src/test/kotlin/app/revanced/patcher/usage/bytecode/ExampleBytecodeCompatibility.kt

@@ -1,4 +1,4 @@
-package app.revanced.patcher.usage.bytecode.annotation
+package app.revanced.patcher.usage.bytecode
 
 import app.revanced.patcher.annotation.Compatibility
 import app.revanced.patcher.annotation.Package